Coal or rock drill.



PATENTED MAR; 3. 1903- I L K KOONTZ. GOAL 0R ROCK DRILL. APPLICATIONFILED MAB 7, 1901.

N 0 MODEL.

mm T r I NV EN TOFL. Z

UNITED STATES PATENT OFFICE.

LOUIS K. KOONTZ, OF ALLEGHENY, PENNSYLVANIA, ASSIGNOR TO MARTIN HARDSOCGMANUFACTURING COMPANY, LIMITED, OF ALLEGHENY,

PENNSYLVANIA.

COAL OR ROCK DRILL.

SPECIFICATION forming part of Letters Patent No. 721,895, dated March 3,1903.

Application fil ed March 7, 1901.

To aZZ whom it may concern.-

Be it known that I, LoUIs K. Koon'rz, a citizen of the UnitedStates,residing atAllegheny, in the county of Allegheny and State ofPennsylvania, have invented new and useful Improvements in Coal or RockDrills, of which the following is a specification.

This invention relates to coal and rock drills; and the object thereofis to provide antomatically-variable feed mechanism for operatingdirectly on the active portion of the twist drill or auger and adaptedto be actuated by rotation of the drill without regard to the manner inwhich power is applied to the latter.

The invention consists in the novel structural features and combinationand arrangement of parts hereinafter fully described and claimed, andillustrated by the accompanying drawings, wherein Figure l is a verticallongitudinal sectional view of myimproved mechanism shown in position ona drill. Fig. 2 is a plan view of the same. Fig. 3 is avertical-cross-sectional view taken on line 3 3 of Fig. 1.

Referring to the drawings, 2 representsa full-length twist-drillcontinuous from end to end and provided at its inner end with bit 3 andat its outer end with crank 3. Any desired form of bit may be used, anda ratchetlever or other actuating device (not shown) may be substitutedfor the crank.

4 represents a bearing-head provided with side trunnions 5, adapted torest in notched arms6 of chair 7, the latter being mounted on grip-bar 8in usual manner. It will be understood, however, that so far as thepresent invention is concerned it is immaterial how head 4 is supported,so that when preferred a vertical post, Well known in the art, may beused in place of bar 8. Revolubly mounted in the bore of head 4 issleeve or barrel 9, having at its inner end the annular shoulder 10,adapted to bear against the inner face of head 4. Adjustable in theouter portion of this sleeve are the oppositely-positioned screws 11,which are engaged by opposite edges of the drill-twist, as clearly shownin Fig. 3, these screws comprising the only impediment to the freelongitudinal movement of drill 2 through sleeve 9. Instead of Serial No.50,186. (No model.)

the screws the sleeve may be cast with integral inward projections, aswill be understood, though screws are preferable, as they may beadjusted to compensate for wear. Also by means of these screwstwist-drills varying in size may be used without providing a specialsleeve for each size, it being only necessary to adjust the screwsaccording to the size used.

Immediately behind head 4 sleeve 9 is formed with the annular peripheraldepression 12 to receive the fiat spring 13. The latter is here showndoubled upon itself around hinge-pin 14, projecting from the head 4. Thefree end of the spring extends beneath lug l5, projecting from head 4,with adjustingscrew 16 working through the lug and bearing on the springand operating to either increase or diminish the frictional engagementof the spring with sleeve 9. The spring bearing in depression 12prevents the sleeve from dropping forward in head 4. I do not restrictmyself to the spring mechanism here shown for frictionally uniting head4 and sleeve 9, as this may be accomplished in various ways withoutdeparting from the spirit or scope of my invention.

In operation rotary motion is applied directly to the drill by the crankor other actuating device at the outer end thereof. When the resistanceagainst rotation of sleeve 9 in head 4, caused by spring 13, is greaterthan the resistance of the coal or rock against the bit,sleeve 9 willremain stationary, and screws 11, engaging the drill-twist, will causethe drill to feed forward while rotating. On the other hand, when theresistance to the bit is greater than the resistance offered by spring13, sleeve 9 will rotate with the drill, and the latter will notadvance. The resistance by the spring may be regulated by screw 16 tomeet various working conditions. In practice the opposing forces-to wit,the mineral and the springare usually so balanced by means of the springadjustment that sleeve 9 will maintain a practically constant rotation,though at slower speed than the drill, whereby the latter is advanced orfed forward as rapidly as desired.

With my improvement the operation of drilling is greatly simplified andlabor lessened. Vith the apgliances now generally used drilling isstarted with a short augersection, and when the hole has advanced to thedepth thereof the drill is withdrawn and a longer auger-sectioninserted, and to secure the desired depth it may be necessary to backout again and insert a third and longer anger or couple together the twoauger-sections first used. All this is occasioned by the necessary useof a screw-threaded feedbar, to which the anger is coupled, and shouldit be attempted to start in the first instance with a longauger-section, together with its coupled feed-bar, the machine would beof such length that there would not be sufficient room therefor in themine-rooms, and in such event also the feed mechanism would be too farremoved from the face of the coal to secure an efiicient Working. Henceit is always desirable to have the feed mechanism as close to the coalas practicable,so that the drill may be held steady and prevented fromspringing laterally or \Vabbling. \Vith my improvements herein proposeda full-length auger may be used in the first instance, as it comprisesthe full length of the machine, no feedbar being necessary. Also thefeed mechanism may be positioned "s close to the face of the coal asdesired, as it operates alike on all portions of the twist-drill. Thefeed-bar being eliminated, the cost of the machine is much less thanthose now used.

By the terms twist-drill and twist drill and anger occurring in eitherthe specification or claims I refer not only to those drills formed ofbar metal which has been spirally twisted to secure the desired shape,as said terms in the sense herein employed contemplate all forms ofdrills having spiral or v0- lute depressions, and while it is theprimary object of the present invention to dispense with a feed-bar yetit will be understood that the automatically-variable feed mechanismmay, if desired, be used on and in conjunction with such bar withoutdeparting from the scope of the invention.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is

1. The combination of a bearing-head having a circular opening, a sleeveof greater length than the head and mounted between its ends to rotatein the head, an annular enlargement at one end of the sleeve adapted tobear against one face of the head, a friction device secured to theopposite face of the head, the projecting portion of the sleeve beingformed with an annular depression which receives the friction devicethereby confining the sleeve against longitudinal movement, means foradjusting said device, and a drill extending through the sleeve andoperatively engaging the same, substantially as described.

2. The combination of a bearing-head having a circular opening, a sleeveof greater length than the head and extending therethrough and rotatabletherein one end of said sleeve being formed with an annular flangeadapted to bear against one face of the head, a flat spring secured tothe opposite face of the head and extending transversely across thesame, the projecting portion of the sleeve being formed with an annulardepression to receive the flat spring and be held thereby againstlongitudinal displacenxwnt, means for adjusting the spring forincreasing or diminishing the pressure thereof on the sleeve and a drillextending through the sleeve and operatively engaging the same,substantially as described.

3. The combination of head 4: formed with a circular opening, elongatedsleeve 9 fitting and adapted to rotate in the head-opening and formedwith end flange 10 which bears against one face of head 4, a combinedtension and securing device for the sleeve for retarding rotation andfor holding the sleeve against longitudinal displacement within head 4,atwist augeror drill extending through the sleeve, and screws radiallyadjustable in sleeve 9 which engage the drill-twist, the adjustment ofsaid screws compensating for wear and providing a range of adjustmentwhereby drills of varying size may be used in the same sleeve 9,substantially as described.

4. The combination of a fixed bearing-head, a sleeve revoluble thereinand formed with an annular external shoulder adapted to bear against theforward face of the head, said sleeve being formed with an annularexternal depression at the opposite side of the head, a yielding devicecarried by the head adapted to bear in said depression for retardingrotation of the sleeve and :"or holding the same against longitudinaldisplacement, internal projections on the sleeve, and a twistdrillWorking through the sleeve and operatively engaged by the saidprojections, substantially as described.

5. Feeding mechanism for rotating forwardly-advancing devices comprisinga head or body having an unthreaded bore, a stem having a spiralexterior rotatable and movable longitudinally in the said bore,and:radiallyadjustable devices carried by the head or body adapted toengage the spiral convolutions of the stem, substantially as described.

6. The combination of a rotatable longitudinally-fixed sleeve, means forretarding rotation thereof, a twist-drill extending through the sleeve,and inwardly-projecting radiallyadjustable devices carried by the sleeveand adapted to be engaged by the drill-twist, substantially asdescribed.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

LOUIS K. KOONTZ.

Witnesses:

J. M. NESBIT, ALEX. S. MABON.

